Brite industrial drill bits feature premium grade high speed steel for general purpose drilling in wood, metal and plasticNo center punch needed: 135° Quick-Cut Points are self-centering and penetrate faster with less pressure...will not "walk" or "wander"at the starting surfaceGround flats on the shank providing tight chucking, even with keyless chucksIncludes sizes 1/16" to 1/2" by 64ths, with a 3/8" reduced shanks in a heavy duty metal index